Loop Carousel with Related Items

I’ve proven that the queries I’m using are working just fine, as you can see with the shortcode implementation directly below the carousel.

I see there is content under a heading saying “Shortcode” in the linked page, but it is not clear how that is related, because a shortcode does not override a WP_Query like these filters, and the shortcode code is not in this post for reference.

add_action('elementor/query/locations_by_token', 'aa_query_locations_by_token', PHP_INT_MAX, 1);

add_action('elementor_pro/posts/query/locations_by_token', 'aa_query_locations_by_token', PHP_INT_MAX, 1);

add_action('elementor_pro/query/locations_by_token', 'aa_query_locations_by_token', PHP_INT_MAX, 1);

It’s not clear whether all these filters are necessary or not. Focus on one and verify it is running at all. According to the linked documentation, it should be the first, and locations_by_token must be specified in the Query ID field of the module you are attempting to filter, as shown in the screenshot at https://developers.elementor.com/docs/hooks/custom-query-filter/

I know that the first query hook DID work at some point, but when I upgraded Elementor Pro recently, it stopped working. 

Sounds like Elementor team may be able to provide more information if you ask a more specific question about one filter at a time and any differences between the version you upgraded from and to.

functions.php:

There appears to be a lot of shorthand code and optimizations which could break in many ways. Without access to the debug output or data structure, below are some comments to consider or check regarding things that could possibly go wrong:

/** TOKEN page → Related LOCATIONS (field_id=86669) */

function aa_query_locations_by_token($query){

  global $wpdb;

  // Resolve token ID even in AJAX preview

The code begins with a comment that this query should be occurring on a token page, but then attempts to get the token ID several different ways, and attempts to get the related IDs by a field ID 86669…

$token_id = get_queried_object_id();

  if (!$token_id && !empty($GLOBALS['post']->ID)) $token_id = (int) $GLOBALS['post']->ID;

  $ids = $token_id ? $wpdb->get_col($wpdb->prepare(

    "SELECT pr.related_item_id

     FROM {$wpdb->prefix}podsrel pr

     WHERE pr.field_id = %d AND pr.item_id = %d

     ORDER BY pr.weight ASC", 86669, $token_id

  )) : [];

  $ids = array_map('intval', array_unique($ids));

  // Defensive: filter to published oum-location only

  if ($ids) {

    $placeholders = implode(',', array_fill(0, count($ids), '%d'));

    $rows = $wpdb->get_col($wpdb->prepare(

      "SELECT ID FROM {$wpdb->posts}

       WHERE ID IN ($placeholders)

         AND post_type = 'oum-location'

         AND post_status = 'publish'",

      ...$ids

    ));

    $ids = array_map('intval', $rows);

  }

• Did this logic actually result in finding the IDs of the desired objects of post type oum-location? Try outputting $ids to verify.
• If no $ids, did $token_id resolve correctly? If you’re not actually on a token singular template, it may be sufficient to use get_the_ID() to get the token ID, skipping the other logic.
• The code below Defensive: can be removed, as you already set the post type and post_status on $query in the following lines.
• It’s not necessary to guess at what values exist or not on WP_Query; you can override the object with a fresh instance.

Without knowing your exact data structure or where this is being queried, I would replace the entire function with something like the code below, assuming the post type is token and the relationship field name is rel_locations:

<?php

function aa_query_locations_by_token( $query ) {
  $token_post_type = 'token';
  $location_field_name = 'rel_location';

  if ( $token_post_type === get_post_type( get_the_ID() ) ) {
    $token_id = get_the_ID();
  }else {
    $token_id = get_queried_object_id();
  }

  $location_ids = get_post_meta( $token_id, $location_field_name );
  if ( empty( $location_ids ) ) {
    $location_ids = [ 0 ];
  }

  aa_emit_footer_note(
    sprintf(
      'Token ID %d is related to location IDs %s through field %s.',
      $token_id,
      implode( ', ', $location_ids ),
      $location_field_name
    )
  );

  $query = new WP_Query(
    [
      'post_type' => 'oum-location',
      'post_status' => 'publish',
      'post__in' => $location_ids,
      'orderby' => 'post__in',
      'posts_per_page' => -1,
      'no_found_rows' => true,
    ]
  );
}
add_action('elementor/query/locations_by_token', 'aa_query_locations_by_token', PHP_INT_MAX, 1);

…if that works, then move on to paging/offsets or additional filters from there. If it doesn’t work, look closer at where the token ID is coming from and whether the post types and IDs are as expected.